Indeed, viral infection is accompanied by the reprogramming of host cell metabolism and, above all, by the perturbation of redox metabolism; on one hand, the virus induces ROS-generating enzymes such as NADPH oxidase (NOX) and xanthine oxidase (XO), on the other hand, the antioxidant defenses are curtailed, creating unbalanced antioxidant levels [26]. The gene discussed is XDH; the disease is viral infectious disease.